1. Field of Invention
This invention resides in the field of electrophoretic transfer of macromolecules, such as proteins and nucleic acids, and relates in particular to the transfer of polypeptide species from a matrix following electrophoresis, during which the polypeptide species were separated, to a second substrate for further detection and characterization.
2. Description of Prior Art
Electrophoresis is a fundamental tool in the modern laboratories of biological research. Typically, macromolecules such as proteins and nucleic acids become separated during electrophoresis as they migrate through a solid matrix in an electrical field. At the conclusion of an electrophoresis procedure, the macromolecules are found in distinct locations of the matrix depending on characteristics of the molecules such as molecular weight and electrical charge. Further studies of such macromolecules often require that the molecules be relocated to a second substrate where better reaction conditions are permitted. Electroblotting is one example of the post-electrophoresis transfer.
Numerous methods of electroblotting are well known and frequently practiced in the art. The transfer process is usually carried out in a liquid or semi-liquid environment where the macromolecules within an electrophoresis matrix, such as a polyacrylamide gel, is transferred to a second matrix suitable for further analysis, such as a membrane of nitrocellurose, nylon, etc. The movement of the macromolecules from the electrophoretic matrix to the analytical matrix is facilitated by an aqueous transfer buffer, which plays an important role in the efficiency of the transfer.
Various publications describe transfer buffers useful for the purpose of electroblotting, see, e.g., Towbin et al. (1979) Proc. Natl. Acad. Sci. USA 76:4350-4354; Timmons and Dunbar (1990) Methods in Enzymology 182:679-688. The present inventors provide a new aqueous transfer buffer that offers improved transfer efficiency, especially for polypeptides of relatively low molecular weight range.